As we learned back when researchers were creating working blood vessels with a 3D printer, the process is as simple as it is complex. It starts with the growth of cells. The 3D printer comes into play when they are used to create a layered structure that’s then layered with cells that attach to the structure and turn it into the organ.

With our current technology, it’s estimated that it would take 10 days to print a liver. As technology improves, it’s estimated that scientists could print a liver in three hours. That’s great news for the thousands of people who are waiting for a live transplant to save their life.

The creation of organs through 3D printing has another, less talked about function, as well. If we could test drugs on 3D printed human livers, it would save millions of dollars and years of time that it takes to develop and test new drugs on animals before it’s even considered for human testing.

As you can see, 3D printing is seriously the most important invention of the 20th century.